Related Experiment Video
Updated: Nov 23, 2025
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
6.8K
Experimental study on static and dynamic mechanical properties of phosphogypsum
Ting Lu1,2, Wensong Wang3,4, Zuoan Wei5,6
1State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
Environmental Science and Pollution Research International
|January 4, 2021
Summary
Phosphogypsum (PG) exhibits medium compressibility and weak permeability. Its engineering properties are generally poorer than natural soils, impacting the stability of PG dams.
Area of Science:
- Geotechnical Engineering
- Environmental Science
Background:
- Phosphogypsum (PG) is a major solid waste from phosphoric acid production.
- Increasing phosphate fertilizer demand leads to larger PG accumulation in ponds.
Purpose of the Study:
- To characterize the geotechnical properties of PG.
- To provide data for the stability analysis of phosphogypsum dams.
Main Methods:
- Laboratory geotechnical tests: permeability, compressibility, triaxial shear, and dynamic triaxial tests.
- Consideration of PG solubility and dehydration during sample preparation.
Main Results:
- PG shows medium compressibility and medium to weak permeability.
- Shear strength and deformation modulus increase with dry density and confining pressure.
- The Davidenkov model better describes PG's dynamic properties compared to the Hardin-Drnevich model.
Conclusions:
- PG's engineering mechanical properties are relatively poor compared to tailings and natural soils.
- Uniform particle distribution and stacking structure may explain PG's weaker performance.
- Findings are crucial for assessing phosphogypsum dam stability.
Keywords:
Damping ratioDynamic shear modulusGeotechnical testLiquefactionShear strengthWaste managementMore Related Videos
Related Concept Videos
01:17Mortar Properties
283
Mortar properties encompass a range of characteristics crucial for construction and masonry work, including workability, water retention, bond strength, durability, compressive strength, volume change, and appearance. Workability refers to mortar's ability to be easily applied and manipulated without sagging or falling off surfaces, which is important for efficient masonry unit placement and alignment. Water retention is essential to prevent the mortar from losing moisture too quickly to...
283
01:16Dynamic Modulus of Elasticity of Concrete
705
The dynamic modulus of elasticity assesses how a concrete structure deforms under impact or dynamic loads. It is typically higher than the static modulus of elasticity, measured under slow, steady loading conditions.
The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x 4 x 20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by a...
The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x 4 x 20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by a...
705
01:17Soundness of Cement
363
The soundness of cement refers to the ability of cement paste to retain its volume after setting. Unsound cement can lead to expansion and structural damage due to the presence of free lime, magnesia, and calcium sulfate. Free lime hydrates very slowly, expanding and causing unsoundness, which is difficult to detect because it intercrystallizes with other compounds. Magnesia also reacts with water, forming crystals that can disrupt the cement's structure. Calcium sulfate can create...
363
01:20Strength of Cement
314
Strength tests for cement are not performed directly on neat cement paste due to difficulty in obtaining consistent, reliable specimens. Instead, cement is typically tested in the form of cement-sand mortar.
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
314
01:15Fineness of Cement
337
The fineness of cement directly influences the rate of hydration, as the hydration begins at the surface of the cement particles. In addition to hydration, the fineness of cement is vital for various properties of concrete including workability, gypsum requirement, and long-term behavior. The fineness of cement is represented in terms of the specific surface of cement which is typically measured in square meters per kilogram, with several methods available for this determination.
Direct...
Direct...
337